190 Report OF THE BoTANICAL DEPARTMENT OF THE 
The infested currant plantation was adjoined on the west by a 
plantation of gooseberries containing many different varieties. Only 
one variety (Pearl) was affected and this but slightly. 
In another part of the Station grounds, near the Director’s resi- 
dence and about forty rods east of the infested plantation, there 
are planted sixteen different species of Ribes, including R. aureum, 
but neither PR. nigrum nor Rk. rubrum. Of these only one species, 
R. irriguum, was affected. There were two plants of R. wriguum 
and both were severely attacked. 
A large quantity of the rusted leaves was preserved. Specimens 
will be distributed in Fungi Columbiani, Century 24. 
DESCRIPTION OF THE FUNGUS. 
The fungus Cronartium ribicola was first described and named 
by Dietrich fifty years ago.2 It appears during the summer and 
autumn as a conspicuous orange-colored powder on the under sur- 
face of the leaves of various species of Ribes (currants and goose- 
berries). Two formes of spores, uredo- and teleutospores, are 
produced on Ribes leaves. The uredospores are ellipsoidal to 
ovoid, 19-35x14-224 with orange-colored contents and borne in sori 
forming pustules. The teleutospores are elongated, unicellular and 
massed together into peculiar orange-colored columnar processes 
which attain a maximum length of about two millimeters. These 
processes are usually curved. To the unaided eye they appear like 
coarse, yellow plant hairs, hence the German name “ Filzrost”’ 
(felt-rust) 4 
Another form (the aecidium form) of the currant rust fungus 
occurs on the trunks and branches of Pinus spp., especially the 
white pine,® Pinus strobus, producing a disease called blister rust 
(Blasenrost of the Germans). The pine-inhabiting form was first 
described by Klebahn in 1887 as a distinct species and by him 
* Dietrich (10). The number in parenthesis refers to the bibliography. 
*See Plates VII and VIII. 
*In Europe Pinus strobus is universally known as the Weymouth pine, 
being named after Lord Weymouth who took up its cultivation actively when 
it was first introduced into England in 1705. (See Garden and Forest, 
32536. 1800.) 
